From: Eric Sandeen <sandeen@redhat.com>
Date: Wed, 14 May 2014 17:39:07 +0000 (-0500)
Subject: btrfs-progs: mkfs: allow UUID specification at mkfs time
X-Git-Url: http://repo.or.cz/w/btrfs-progs-unstable/devel.git/commitdiff_plain/a03901849f868c65f845325fcaeb3d25c6896759
btrfs-progs: mkfs: allow UUID specification at mkfs time
Allow the specification of the filesystem UUID at mkfs time.
Non-unique unique IDs are rejected. This includes attempting
to re-mkfs with the same UUID; if you really want to do that,
you can mkfs with a new UUID, then re-mkfs with the one you
wanted.
(Implemented only for mkfs.btrfs, not btrfs-convert).
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[converted help to asciidoc]
Signed-off-by: David Sterba <dsterba@suse.cz>
---
Index: btrfs-progs-v3.14.2/Documentation/mkfs.btrfs.txt
===================================================================
--- btrfs-progs-v3.14.2.orig/Documentation/mkfs.btrfs.txt
+++ btrfs-progs-v3.14.2/Documentation/mkfs.btrfs.txt
@@ -21,6 +21,7 @@ $$[-s|--sectorsize <sectorsize>]$$
$$[-r|--rootdir <rootdir>]$$
$$[-K|--nodiscard]$$
$$[-O|--features <feature1>[,<feature2>...]]$$
+$$[-U|--uuid <UUID>]$$
$$[-h]$$
$$[-V|--version]$$
$$<device> [<device>...]$$
@@ -109,6 +110,10 @@ supported by old kernels.
To see all features run::::
mkfs.btrfs -O list-all
+-U|--uuid <UUID>::
+Create the filesystem with the specified UUID, which must not already exist on
+the system.
+
-V|--version::
Print the *mkfs.btrfs* version and exit.
Index: btrfs-progs-v3.14.2/btrfs-convert.c
===================================================================
--- btrfs-progs-v3.14.2.orig/btrfs-convert.c
+++ btrfs-progs-v3.14.2/btrfs-convert.c
@@ -2240,7 +2240,7 @@ static int do_convert(const char *devnam
goto fail;
}
ret = make_btrfs(fd, devname, ext2_fs->super->s_volume_name,
- blocks, total_bytes, blocksize, blocksize,
+ NULL, blocks, total_bytes, blocksize, blocksize,
blocksize, blocksize, 0);
if (ret) {
fprintf(stderr, "unable to create initial ctree: %s\n",
Index: btrfs-progs-v3.14.2/mkfs.c
===================================================================
--- btrfs-progs-v3.14.2.orig/mkfs.c
+++ btrfs-progs-v3.14.2/mkfs.c
@@ -288,6 +288,7 @@ static void print_usage(void)
fprintf(stderr, "\t -r --rootdir the source directory\n");
fprintf(stderr, "\t -K --nodiscard do not perform whole device TRIM\n");
fprintf(stderr, "\t -O --features comma separated list of filesystem features\n");
+ fprintf(stderr, "\t -U --uuid specify the filesystem UUID\n");
fprintf(stderr, "\t -V --version print the mkfs.btrfs version and exit\n");
fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
exit(1);
@@ -351,6 +352,7 @@ static struct option long_options[] = {
{ "rootdir", 1, NULL, 'r' },
{ "nodiscard", 0, NULL, 'K' },
{ "features", 1, NULL, 'O' },
+ { "uuid", 0, NULL, 'U' },
{ NULL, 0, NULL, 0}
};
@@ -1273,11 +1275,12 @@ int main(int ac, char **av)
int dev_cnt = 0;
int saved_optind;
char estr[100];
+ char *fs_uuid = NULL;
u64 features = DEFAULT_MKFS_FEATURES;
while(1) {
int c;
- c = getopt_long(ac, av, "A:b:fl:n:s:m:d:L:O:r:VMK",
+ c = getopt_long(ac, av, "A:b:fl:n:s:m:d:L:O:r:U:VMK",
long_options, &option_index);
if (c < 0)
break;
@@ -1346,6 +1349,9 @@ int main(int ac, char **av)
source_dir = optarg;
source_dir_set = 1;
break;
+ case 'U':
+ fs_uuid = optarg;
+ break;
case 'K':
discard = 0;
break;
@@ -1368,6 +1374,20 @@ int main(int ac, char **av)
"The -r option is limited to a single device\n");
exit(1);
}
+
+ if (fs_uuid) {
+ uuid_t dummy_uuid;
+
+ if (uuid_parse(fs_uuid, dummy_uuid) != 0) {
+ fprintf(stderr, "could not parse UUID: %s\n", fs_uuid);
+ exit(1);
+ }
+ if (!test_uuid_unique(fs_uuid)) {
+ fprintf(stderr, "non-unique UUID: %s\n", fs_uuid);
+ exit(1);
+ }
+ }
+
while (dev_cnt-- > 0) {
file = av[optind++];
if (is_block_device(file))
@@ -1514,7 +1534,7 @@ int main(int ac, char **av)
process_fs_features(features);
- ret = make_btrfs(fd, file, label, blocks, dev_block_count,
+ ret = make_btrfs(fd, file, label, fs_uuid, blocks, dev_block_count,
nodesize, leafsize,
sectorsize, stripesize, features);
if (ret) {
Index: btrfs-progs-v3.14.2/utils.c
===================================================================
--- btrfs-progs-v3.14.2.orig/utils.c
+++ btrfs-progs-v3.14.2/utils.c
@@ -93,12 +93,41 @@ static u64 reference_root_table[] = {
[6] = BTRFS_CSUM_TREE_OBJECTID,
};
-int make_btrfs(int fd, const char *device, const char *label,
+int test_uuid_unique(char *fs_uuid)
+{
+ int unique = 1;
+ blkid_dev_iterate iter = NULL;
+ blkid_dev dev = NULL;
+ blkid_cache cache = NULL;
+
+ if (blkid_get_cache(&cache, 0) < 0) {
+ printf("ERROR: lblkid cache get failed\n");
+ return 1;
+ }
+ blkid_probe_all(cache);
+ iter = blkid_dev_iterate_begin(cache);
+ blkid_dev_set_search(iter, "UUID", fs_uuid);
+
+ while (blkid_dev_next(iter, &dev) == 0) {
+ dev = blkid_verify(cache, dev);
+ if (dev) {
+ unique = 0;
+ break;
+ }
+ }
+
+ blkid_dev_iterate_end(iter);
+ blkid_put_cache(cache);
+
+ return unique;
+}
+
+int make_btrfs(int fd, const char *device, const char *label, char *fs_uuid,
u64 blocks[7], u64 num_bytes, u32 nodesize,
u32 leafsize, u32 sectorsize, u32 stripesize, u64 features)
{
struct btrfs_super_block super;
- struct extent_buffer *buf;
+ struct extent_buffer *buf = NULL;
struct btrfs_root_item root_item;
struct btrfs_disk_key disk_key;
struct btrfs_extent_item *extent_item;
@@ -125,7 +154,20 @@ int make_btrfs(int fd, const char *devic
memset(&super, 0, sizeof(super));
num_bytes = (num_bytes / sectorsize) * sectorsize;
- uuid_generate(super.fsid);
+ if (fs_uuid) {
+ if (uuid_parse(fs_uuid, super.fsid) != 0) {
+ fprintf(stderr, "could not parse UUID: %s\n", fs_uuid);
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!test_uuid_unique(fs_uuid)) {
+ fprintf(stderr, "non-unique UUID: %s\n", fs_uuid);
+ ret = -EBUSY;
+ goto out;
+ }
+ } else {
+ uuid_generate(super.fsid);
+ }
uuid_generate(super.dev_item.uuid);
uuid_generate(chunk_tree_uuid);
Index: btrfs-progs-v3.14.2/utils.h
===================================================================
--- btrfs-progs-v3.14.2.orig/utils.h
+++ btrfs-progs-v3.14.2/utils.h
@@ -40,7 +40,7 @@
#define BTRFS_UUID_UNPARSED_SIZE 37
int make_btrfs(int fd, const char *device, const char *label,
- u64 blocks[6], u64 num_bytes, u32 nodesize,
+ char *fs_uuid, u64 blocks[6], u64 num_bytes, u32 nodesize,
u32 leafsize, u32 sectorsize, u32 stripesize, u64 features);
int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid);
@@ -101,5 +101,5 @@ int get_btrfs_mount(const char *dev, cha
int find_mount_root(const char *path, char **mount_root);
int get_device_info(int fd, u64 devid,
struct btrfs_ioctl_dev_info_args *di_args);
-
+int test_uuid_unique(char *fs_uuid);
#endif